Method of making an integrated circuit package employing a transparent encapsulant

ABSTRACT

A method of making an integrated circuit package for EPROM, CCD, and other optical integrated circuit devices is disclosed. First, a substrate base having metallized vias extending there through is provided. Second, an integrated circuit die is affixed to a first surface of the substrate, and is electrically connected to the metallized vias. Third, a bead of a viscous adhesive material is applied onto the substrate around the device. The bead covers the side surfaces of the device, the periphery of the upper first surface of the device, and the bond wires. The bead and the upper first surface of the die form a cavity above the die. Fourth, a layer of a transparent encapsulating material is deposited onto the die, within the cavity formed by the bead. Fifth, the encapsulating material is hardened, and subsequently forms an exterior surface of the package. The transparent encapsulating material allows light to illuminate the light sensitive circuitry of the device.

CROSS-REFERENCE TO RELATED APPLICATION

This is a divisional application of prior U.S. patent application Ser.No. 08/926,507, filed Sep. 9, 1997, entitled "Integrated Circuit PackageEmploying A Transparent Encapsulant," now issued as U.S. Pat. No.5,962,810.

FIELD OF THE INVENTION

The present invention relates to integrated circuit packages, and inparticular to a package for an integrated circuit device havingcircuitry whose functioning requires the transmission of light throughthe package.

BACKGROUND OF THE INVENTION

Integrated circuit devices are typically housed in packages. Typicalpackages are made of plastic, ceramic, or metal. The packages includeinternal and external conductive structures, such as metallized vias,metal traces, bond wires, and solder interconnection balls or leadlesschip carrier ("LCC") pads, for electrically connecting the integratedcircuit device in the package to external circuitry, such as a circuitboard.

Certain types of integrated circuit devices, such as erasableprogrammable read-only memory devices ("EPROM"), charge coupled devices("CCD") or optical sensing devices, such as those used in documentscanners, fingerprint recognition equipment, or other consumer products,require a selected or continuous transmission of light of a selectedfrequency through the top surface of the package onto the surface of theintegrated circuit die within the package. Typically, the packages forsuch integrated circuit devices have a glass or quartz window in theotherwise opaque top surface of the package. This transparent window islocated above the die, and the selected frequency of light passesthrough the window and impinges on the top surface of the die.Unfortunately, packages having such glass or quartz inserts arerelatively expensive to fabricate, which raises the cost of the productsin which the integrated circuit devices are used. A less expensivealternative would have wide application.

SUMMARY OF INVENTION

Embodiments of an improved package for integrated circuit devices, suchas EPROM and CCD or other optical devices whose functioning requires aselective or continuous transmission of light through a portion of thepackage, are disclosed. Exemplary methods of making such packages arealso described.

The package has a planar insulating substrate base, which may be formedof an epoxy laminate or ceramic. The substrate has a first surface andan opposite second surface. Metallized vias extend through thesubstrate. An integrated circuit die having light-sensitive circuitry,such as a die for a CCD device, is affixed to the first surface of thesubstrate. Bond wires are installed which electrically connect theconductive bonding pads on the die to conductive structures on the firstsurface of the substrate, such as metal traces and contact pads. Theseconductive structures are in turn electrically connected to themetallized vias through the substrate. Conductive structures on thesecond surface of the substrate, such as solder interconnection balls orLCC pads, for connecting the package to external circuitry areelectrically connected to the metallized vias and hence to the die.

After the bond wires are installed, a bead of an adhesive material suchas epoxy plastic is deposited onto the first surface of the substrateperipherally around the die. The bead covers the peripheral sidesurfaces of the die and the periphery of the upper first surface of thedie, including the bonding pads of the die. The bead also covers thebond wires and the conductive structures on the first surface of thesubstrate. The height of the bead around the die exceeds both the heightof the die above the substrate and the height of the normally bowed bondwires, thus forming a central cavity above and with the upper firstsurface of the die.

After a step of hardening the bead material, a layer of a transparentencapsulating material, such as clear TEFLON® polymeric resin, isdeposited onto the die, within the central cavity formed by the bead andthe upper first surface of the die. The layer of transparentencapsulating material is subsequently hardened, forming a solidtransparent exterior package surface above the optical sensing circuitryof the die.

An alternative method of making the package employs a relatively largersubstrate having a plurality of sites which are adapted for theformation of an array of individual integrated circuit packages. Eachsite has one or more conductive structures on its first and secondsurfaces, and one or more metallized vias extending through thesubstrate. An integrated circuit die is attached to each site of thearray, and is electrically connected to the metallized vias through thesubstrate. A bead of adhesive material is deposited onto the firstsurface of the substrate so that a bead surrounds each die in the array.The beads cover the side surfaces of the dies, the periphery of theupper first surface of the dies, and the bond wires. Together, the beadand the upper first surface of the die define a cavity above each dieinto which a layer of encapsulating material is deposited.

One way of applying the bead material is to deposit crisscrossingperpendicular beads of the adhesive material on the substrate adjacentto all sides of the dies in the array. The rows and columns of beadmaterial meld together, forming a continuous bead around each die in thearray. After the bead material is hardened, a layer of a transparentencapsulating material is placed onto the die within the cavity formedby the bead and the first surface of the die. The encapsulating materialis then hardened, and the individual packages in the array areseparated.

Among other virtues, the packages and methods described herein provide alower cost solution to the problem of designing reliable packages forEPROM, CCD, and other optical devices.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional side view of an integrated circuit package.

FIG. 2 is a plan view of an integrated circuit package prior toencapsulation.

FIG. 3 is a flow chart of a method of assembling an integrated circuitpackage.

FIG. 4 is a top view of an array of incomplete integrated circuitpackages, before bead material is applied onto the array.

DETAILED DESCRIPTION

FIG. 1 is a cross-sectional side view of an exemplary integrated circuitpackage 10 in accordance with the present invention. Substrate 11 formsan insulating base of package 10. Substrate 11 has an upper firstsurface 12 and a lower second surface 13. Substrate 11 may be formed,for example, of a conventional epoxy laminate or ceramic. Examples ofsuitable substrates include Mitsubishi BT, Arlon 45N, and Nelco BTlaminate substrates.

An exemplary thickness of substrate 11, between first surface 12 andsecond surface 13, is between 0.36 mm and 0.56 mm, but the thickness ofsubstrate 11 may vary depending on the application. The perimeter ofsubstrate 11 may be a variety of shapes, again depending on thepackaging application. For example, the perimeter of substrate 11 may besquare or rectangular.

Integrated circuit die 14 rests on and is affixed to first surface 12 ofsubstrate 11. Die 14 has an upper first surface 21 containing peripheralbonding pads 19, peripheral side surfaces 22, and a lower second surface23 opposite first surface 21. Conventional epoxy die attach compound,such as QMI 696 available from the QMI Company of San Diego, Calif., maybe used to affix lower second surface 23 of die 14 to first surface 12of substrate 11.

Typically, EPROM, CCD or other optical integrated circuit dies havevision cells or other light-sensitive circuitry on their upper surfaces,which must be selectively or continuously exposed to light of a selectedfrequency for some functioning of the completed device. In FIG. 1, suchcircuitry is exemplified by polyimide vision cell 24 on a centralportion of upper first surface 21 of die 14. Other non-opticalcircuitry, not shown in FIG. 1, may also be exposed on first surface 21of die 14, depending on the application.

Conductive metallized via 15 extends through substrate 11 between firstsurface 12 and second surface 13. Via 15 may be formed, for example, bydrilling a hole through substrate 11 and plating the hole with metal,such as copper, using conventional methods. Via 15 provides a conductivepath for electrically connecting conductive structures on first surface12 and second surface 13 of substrate 11.

In FIG. 1, conductive structures on or adjacent to first surface 12 ofsubstrate 11 electrically connect die 14 to metallized via 15. Forexample, at the intersection of via 15 and first surface 12 of substrate11, a first end of a metal trace 16 is electrically connected to via 15.Metal trace 16 extends laterally away from via 15, and its second end iselectrically connected to a metal contact 17 on first surface 12 ofsubstrate 11. The term "electrically connected" is used broadly hereinto mean a conductive path exists between the "electrically connected"structures, which may be due to a direct or indirect physicalconnection.

Contact 17 is electrically connected to a first end of a metal bond wire18. An opposite second end of bond wire 18 is electrically connected toa conductive bonding pad 19 on a peripheral portion of upper firstsurface 21 of die 14.

Metal trace 16 and metal contact 17 may be formed, for example, ofcopper that is plated on first surface 12 of substrate 11 usingconventional electroplating methods. Bond wire 18 may be formed of goldor aluminum.

A typical package like FIG. 1 will have multiple metallized vias 15,metal traces 16, contacts 17, bond wires 18, and bonding pads 19, thenumber of which would depend on the application. For clarity, only twoof each of these structures are shown in FIG. 1.

Metallized via 15 also intersects lower second surface 13 of substrate11. At second surface 13, a first end of metal trace 31 is electricallyconnected to metallized via 15. Metal trace 31 extends laterally onlower second surface 13 away from via 15. A second end of metal trace 31is electrically connected to a planar metal interconnection ball land(not shown), which is also formed on lower second surface 13 ofsubstrate 11. A metallic solder interconnection ball 33 is joined to theland. Interconnection balls 33 are used to electrically connect package10, and hence die 14, to external circuitry such as a circuit board. Inalternative embodiments, an interconnection ball land may be formed onthe lower second surface of the substrate around the metallized via, asopposed to a lateral distance from the via, so that an interconnectionball may be placed directly below the via.

A typical package like FIG. 1 would have multiple metal traces 31, metallands, and interconnection balls 33 on the lower second surface 13 ofits substrate 11, the number of which would depend on the packagingapplication. For clarity, only two of these structures are shown in FIG.1.

The interconnection balls 33 of FIG. 1 are characteristic of a ball gridarray ("BGA") package. Such interconnection balls are generally arrangedin an array pattern, such as X and Y axis rows of balls, on secondsurface 13 of substrate 11. The particular pattern selected may depend,for example, on the external circuitry to which package 10 is ultimatelyelectrically connected.

The interconnections of the various conductive structures describedabove, including metallized vias 15, metal traces 16 and 31, contacts17, bond wires 18, metal lands, and interconnection balls 33, provide anelectrically conductive path between bonding pads 19 of die 14 andinterconnection balls 33. Metallized vias 15 provide the portion of theconductive path that extends through substrate 11.

There are, of course, other ways known to practitioners to electricallyconnect an integrated circuit die (or dies) in a package to conductivestructures on the exterior of the package or to connect the packageitself to external circuitry. As an example, instead of using solderinterconnection balls 33, a patterned array of planar metal contacts maybe formed on lower second surface 13 of substrate 11, as in aconventional leadless chip carrier ("LCC") package. As anotheralternative, instead of using bond wires, tape automated bonding may beemployed.

Returning to FIG. 1, bead 20 is adjacent to and a covers the peripheraledges of die 14 on first surface 12 of substrate 11. Bead 20 has a topfirst portion 25, an opposite lower second portion 26, a outer thirdportion 27, and an inner fourth portion 28 adjacent to die 14. Top firstportion 25 of bead 20 forms a peripheral portion of the top surface ofpackage 10. Lower second portion 26 of bead 20 is on and fixed to firstsurface 12 of substrate 11. Outer third portion 27 of bead 20 forms theperipheral side walls of package 10. Inner fourth portion 28 of bead 20covers side surfaces 22 of die 14, as well as the outer periphery ofupper first surface 21 of die 14, including the interconnections betweenbond wires 18 and bonding pads 19 on die 14.

As shown in FIG. 1, bead 20 protectively covers each metal trace 16,contact 17, bond wire 18, and bonding pad 19 located on or adjacent tofirst surface 12 of substrate 11. Bead 20 also covers side surfaces 22of die 14 and the periphery of upper first surface 21 of die 14,including bonding pads 19. Bead 20 does not, however, cover the centralportion of upper first surface 21 of die 14 where polyimide vision cell24 is located, to avoid interference with the light-sensitivefunctioning of vision cell 24. The height of bead 20 above first surface12 of substrate 11 exceeds the height of die 14 and bond wires 18 abovefirst surface 12. Accordingly, bead 20 and upper first surface 21 of die14 together form and define a cavity above die 14, into which a thinlayer of transparent encapsulating material 29 is deposited.

FIG. 2 is a top view of an incomplete package 10, before a transparentencapsulant is placed onto die 14. In FIG. 2, bead 20 surrounds die 14,contacting side surfaces 22 of die 14 all the way around die 14. Toillustrate that bead 20 also covers the periphery of upper first surface21 of die 14, the periphery of first surface 21 of die 14 is shown bydashed lines. Although die 14 and bead 20 are shown as having squareperimeters in FIG. 2, the perimeters of die 14 and bead 20 may varydepending on the application. For example, die 14 and bead 20 may haverectangular perimeters.

Bead 20 is formed of a material that is adhesive. The material of bead20 should also be somewhat viscous and flowable when initially appliedonto first surface 12 of substrate 11, but should be readily hardenableby air drying or heating or the like so that bead 20 forms solid,protective side and top surfaces of package 10.

An example material useful for bead 20 is epoxy, such as Ciba Nagase9006 epoxy from the Ciba Nagase Company of Japan. Hardening of thisepoxy is normally accomplished by heating for about 60 minutes at 150°C. Other suitable epoxy materials usable for bead 20 include Hysol 4451from Hysol Corporation of City of Industry, Calif. Alternatively,instead of epoxy material, bead 20 may be formed of a silicone rubber,such as silicon rubber number 3140 from the Dow Corning Company.

In FIG. 1, a planar layer of transparent encapsulant 29 covers firstsurface 21 of die 14, including the central portion of first surface 21of die 14 where polyimide vision cell 24 is located. When hardened,encapsulant 29 forms a top exterior surface of package 10.

Encapsulant 29 is contained within the square-sided cavity above die 14which was formed by first surface 21 of die 14 and that part of innerfourth portion 28 of bead 20 whose height above first surface 12 ofsubstrate 11 is greater than the height of die 14 above first surface 12of substrate 11.

In FIG. 1, the exemplary planar upper first surface 30 of encapsulant 29is slightly lower, for example, about 0.005 mm lower, than top firstportion 25 of bead 20, which may provide protection from abrasions tofirst surface 30.

The appropriate thickness of the layer of encapsulant 29 depends, forexample, on the packaging application and the material chosen forencapsulant 29. A typical material appropriate for encapsulant 29 has alight transmission value that is a function of its thickness.

Encapsulant 29 is formed of a material that is adhesive. The material ofencapsulant 29 should be somewhat viscous and flowable when initiallyapplied onto first surface 21 of die 14, but should be hardenable sothat the layer of encapsulant 29 forms a solid, protective top surfaceof package 10 adjacent to die 14.

As discussed above, the EPROM, CCD, and other optical sensing deviceapplications suited for a package such as FIG. 1 require that a surfaceof the packaged die be selectively or continuously exposed to light of aselected frequency. In such applications, the material chosen forencapsulant 29 should be transparent to the particular frequency oflight needed by the application.

In the example of FIG. 1, die 14 has a polyimide vision cell 24 locatedon a central portion of first surface 21 of die 14. As is typical in CCDor other optical sensing applications, such a vision cell requiresexposure to visible light. For such applications, as shown in FIG. 1,encapsulant 29 is formed of a clear material, such as clear TEFLON®synthetic polymeric resin (polytetrafluoroethylene) from the E.I. DupontChemical Company, or an equivalent transparent, protective material. Alayer of TEFLON® resin having a thickness of about 0.20 mm may behardened by heating at a temperature of about 150° C. for about 60minutes. Alternatively, a layer of water white clear epoxy may be usedfor encapsulant 29.

The dimensions of a package like FIG. 1 will vary with the particularpackaging application. As an example, dimensions of components ofpackage 10 may include an approximately 10 mm×10 mm square substrate 11;an approximate 8 mm by 8 mm square die 14; a bead 20 having anapproximate 9 mm×9 mm square perimeter; a bead 20 height between topfirst portion 25 and first surface 12 of substrate 11 ranging fromapproximately 0.60 mm to 0.80 mm; a bead 20 width between outer thirdportion 27 and side surfaces 22 of die 14 ranging from approximately0.60 mm to 0.80 mm; and a relatively thin layer of a transparentencapsulant 29 having a thickness, i.e., a height between upper firstsurface 21 of die 14 and upper first surface 30 of encapsulant 29,ranging from approximately 0.10 mm to 0.30 mm. As an example, thethickness of encapsulant 29 may be 0.20 mm. Again, such dimensions willvary with the packaging application. For example, larger dies typicallyrequire larger packages.

FIG. 3 shows a flow chart for an example method of making a package inaccordance with the present invention. As a first step A in the processshown in FIG. 3, an insulating substrate base is provided havingconductive structures on and between its first and second surfaces. Asan example, substrate 11 of FIG. 1 is provided. In FIG. 1, substrate 11has metal traces 16 and 31, metallized vias 15, contacts 17, metallands, and interconnection balls 33, all of which are electricallyconnected.

As a second step B, an integrated circuit die is provided and placed onthe first surface of the substrate. A conventional epoxy die attachmaterial may be used to affix the die to the substrate.

As a third step C, the integrated circuit die is electrically connectedto the conductive structures on and through the substrate. Using theexample of FIG. 1, bond wires 18 are connected between bonding pads 19on the periphery of die 14 and contacts 17 on substrate 11 so that die15 may be electrically connected to metallized vias 15, and hence tointerconnection balls 33. A conventional bond wire attaching machine maybe used to perform this step.

A fourth step D is the application of a bead of a viscous, hardenable,adhesive material onto the first surface of the substrate, around theintegrated circuit die. The bead should be applied so that its heightrelative to the upper first surface of the substrate exceeds the heightof the die above the substrate. In this way, a cavity is formed abovethe upper first surface of the die into which the transparentencapsulant material may be deposited. FIGS. 1 and 2 show an exemplarybead 20. In those figures, the bead was applied onto the substrate so asto cover the side surfaces of the die and the periphery of the upperfirst surface of die, as well as the bond wires and other conductivestructures on the first surface of the substrate. The bead material doesnot cover the die's light-activated circuitry.

An example bead material is epoxy, such as Ciba Nagase 9006. Such anepoxy bead may be applied using a syringe. Alternatively, a conventionalautodispense machine, such as model 5000 of the Camelot Company or theMillennium model of the Asymtek Company, may be used.

A fifth step E is to harden the bead material. The hardened beadmaterial forms solid, protective side and top surfaces of the package.FIG. 1 shows an example of a solid bead 20. Where epoxy material is usedfor the bead, the step of hardening the bead material may be performedby heating to a temperature of approximately 150° C. for about 60minutes.

After the hardening step, a sixth step F is to apply a layer of aviscous, hardenable, adhesive, and selectively-transparent encapsulatingmaterial onto the exposed upper first surface of the die, within thethree-dimensional cavity formed by the upper first surface of the dieand the now-hardened bead material that surrounds the die. FIG. 1 showshow an embodiment of a package appears after a layer of transparentencapsulant 29 is deposited onto upper first surface 21 of die 14.

Where, for example, the package is for CCD applications or other opticalapplications, the encapsulating material should be clear so as to betransparent to visible light. An example material is clear TEFLON®resin.

The step of applying a layer of a selectively transparent encapsulatingmaterial onto the die may be performed, for example, with a syringe or aconventional autodispense machine. The amount of encapsulating materialused affects the thickness of the layer.

A seventh step G is to harden the layer of encapsulating materialapplied onto the die. This hardening step is performed so that theencapsulating material forms a solid and protective top exterior surfaceof the package. This hardening step may be performed, for example, byheating the package after the encapsulating material is applied.

Depending on the package configuration, as an additional eighth step H,conductive structures such as solder interconnection balls are placed byconventional methods onto metallizations provided on the underside ofthe substrate of the package. For example, FIG. 1 shows a package 10having solder interconnection balls 33 on second surface 13 of substrate11. Alternatively, such conductive structures could be initiallyprovided on the substrate.

In an alternative method, instead of constructing each packageindividually, an array of packages similar to those of FIGS. 1-2 arecreated on a single, relatively larger substrate, and then the array iscut apart to separate the individual packages from each other.

FIG. 4 is a top view of an array 40 of four incomplete packages 10before the step of applying bead material is performed. While array 40shows only four incomplete packages, the number of packages in the arraycan vary, depending, for example, on the size of the substrate and dies.

In this alternate method, the first three steps A-C of FIG. 3 areperformed, i.e. providing an insulating substrate having conductivestructures, providing and affixing an integrated circuit die to thesubstrate, and electrically connecting the die to the conductivestructures on the substrate, except that a larger substrate 41 havingfour sites for placement of integrated circuit dies is provided, and theother steps are repeated to accommodate each of the four integratedcircuit dies that are affixed to substrate 41.

A fourth step is to apply a square bead, like bead 20 in FIGS. 1 and 2,peripherally around each die on array 40 of FIG. 4. In an alternativeembodiment, the step of applying a bead of adhesive material isperformed by applying a first set of parallel beads of adhesive materialadjacent to the integrated circuit dies, and then applying a second setof parallel beads of adhesive material perpendicularly across the firstset of parallel beads, so that a crisscrossing pattern of rows andcolumns of bead material is deposited on the substrate around all sidesof each die. The crisscrossing beads meld to form a continuous beadaround each die in the array. As discussed above, the bead and the upperfirst surface of the die together define a cavity above the die, intowhich the layer of encapsulating material is deposited.

Referring to FIG. 4, after the step of applying bead material ontosubstrate 41 is performed, the fifth through eighth steps E-H of FIG. 3are performed for each package in the array, i.e. the steps of hardeningthe beads, applying the layers of encapsulant within the cavities formedby the beads, hardening the layers of encapsulant, and placingconductive structures such as interconnection balls on the secondsurface of the substrate for each site on the array.

Subsequently, a step of separating the individual packages in the arrayof packages from each other is performed. This step may be performed,for example, by cutting through the substrate and bead material using aconventional wafer saw.

The embodiments of packages and assembly methods described above aremerely examples of the present invention. Artisans will appreciate thatvariations are possible within the scope of the claims set forth below.

What is claimed is:
 1. A method of making an integrated circuit packagecomprising:providing a substrate having a first surface, an oppositesecond surface, and an electrical conductor through the substratebetween said first surface and said second surface; providing anintegrated circuit device, said device having a first surface having alight sensitive portion, and an opposite second surface; placing thesecond surface of the integrated circuit device onto the first surfaceof the substrate; electrically connecting the integrated circuit deviceto the electrical conductor; applying a bead of a viscous adhesivematerial onto the first surface of the substrate around the integratedcircuit device, so that the integrated circuit device is in a cavityformed by the bead and the first surface of the substrate; hardeningsaid adhesive bead; applying a layer of a transparent adhesive materialonto the first surface of the integrated circuit device and within thecavity; hardening the layer of transparent adhesive material; andcutting through both the bead and the substrate with a saw.
 2. Themethod of claim 1, wherein the first surface of the substrate issubstantially planar.
 3. The method of claim 1, wherein the firstsurface of the substrate is planar.
 4. The method of claim 3, whereinthe adhesive bead is applied so that, after hardening the adhesive bead,the bead has a height of about 0.6 mm to 0.8 mm.
 5. The method of claim1, wherein the adhesive bead is applied so that, after hardening theadhesive bead, the bead has a height of about 0.6 mm to 0.8 mm.
 6. Themethod of claim 5, wherein the layer of transparent adhesive material isapplied so that, after hardening the layer, the layer has a thickness ofabout 0.1 mm to 0.3 mm.
 7. The method of claim 5, wherein said adhesivematerial is an epoxy material.
 8. The method of claim 1, furthercomprising electrically connecting a bond wire between the integratedcircuit device and the electrical conductor; andapplying the bead of aviscous adhesive material onto the first surface of the substrate aroundthe device so as to cover the bond wire with the bead material.
 9. Themethod of claim 8, wherein the first surface of the substrate is planar.10. The method of claim 9, wherein the adhesive bead is applied so that,after hardening the adhesive bead, the bead has a height of about 0.6 mmto 0.8 mm.
 11. The method of claim 1, wherein the integrated circuitdevice has a side surface between the first surface and the secondsurface of the integrated circuit device; andapplying the bead of aviscous adhesive material onto the first surface of the substrateincludes covering the side surface and a peripheral portion of the firstsurface of the device with the bead material.
 12. The method of claim11, wherein the first surface of the substrate is substantially planar.13. The method of claim 11, wherein the first surface of the substrateis planar.
 14. The method of claim 11, further comprising electricallyconnecting a bond wire between the integrated circuit device and theelectrical conductor; andapplying the bead of a viscous adhesivematerial onto the first surface of the substrate around the device so asto cover the bond wire with the bead material.
 15. The method of claim14, wherein the first surface of the substrate is substantially planar.16. The method of claim 15, wherein a metal trace is provided on thefirst surface of the substrate that is connected to the electricalconductor through the substrate, and electrically connecting the bondwire includes connecting the bond wire to the metal trace, and applyingthe adhesive bead includes covering the bond wire and the metal tracewith bead material.
 17. The method of claim 14, wherein the firstsurface of the substrate is planar.
 18. The method of claim 17, whereina metal trace is provided on the first surface of the substrate that isconnected to the electrical conductor through the substrate, andelectrically connecting the bond wire includes connecting the bond wireto the metal trace, and applying the adhesive bead includes covering thebond wire and the metal trace with bead material.
 19. A method of makinga plurality of integrated circuit packages comprising:providing asubstrate having a first surface, an opposite second surface, and anarray of sites each adapted for the formation of an integrated circuitpackage; wherein each site has an electrical conductor extending throughsaid substrate between the first surface and the second surface of thesubstrate; providing an integrated circuit device for each site of thearray, wherein each integrated circuit device has a first surface havinga light sensitive portion, and an opposite second surface; placing thesecond surface of one of the integrated devices onto the first surfaceof the substrate at each site; electrically connecting the integratedcircuit device placed on each of the sites to the electrical conductorof the respective site; applying a bead of a viscous adhesive materialonto said first surface of the substrate around each integrated circuitdevice so that each integrated circuit device is in a cavity formed bythe bead and the first surface of the substrate, wherein applying thebead of adhesive material onto the first surface of the substrateincludes applying a plurality of first parallel beads onto the firstsurface of the substrate, with one of said first parallel beads betweenany adjacent devices, and then applying a plurality of second parallelbeads onto the first surface of the substrate in a crisscrossing patternwith said first parallel beads with one of said second parallel beadsbetween any adjacent devices, so that each integrated circuit device issurrounded by bead material; hardening the adhesive bead; applying alayer of a transparent adhesive material onto the first surface of eachintegrated circuit device and within each cavity; hardening saidtransparent adhesive material; and separating the packages.
 20. Themethod of claim 19, wherein separating such bead packages includescutting the substrate.
 21. The method of claim 19, wherein the firstsurface of the substrate is substantially planar.
 22. The method ofclaim 21, wherein separating such bead packages includes cutting thesubstrate.
 23. The method of claim 19, wherein the first surface of thesubstrate is planar.
 24. The method of claim 23, wherein separating suchbead packages includes cutting the substrate.
 25. The method of claim19, wherein separating the packages includes splitting each bead andsplitting the substrate.
 26. The method of claim 25, wherein splittingeach bead and splitting the substrate includes cutting the bead andsubstrate with a saw.
 27. The method of claim 19, further comprisingelectrically connecting a bond wire between each integrated circuitdevice and the electrical conductor of the site for the respectiveintegrated circuit device; andapplying the bead of viscous adhesivematerial onto the first surface of the substrate so that each said bondwire is covered by the bead material.
 28. The method of claim 27,wherein separating the packages includes splitting each bead andsplitting the substrate.
 29. The method of claim 28, wherein splittingeach bead and splitting the substrate includes cutting the bead andsubstrate with a saw.
 30. The method of claim 19, wherein eachintegrated circuit device has a side surface between the first andsecond surface of the integrated circuit device; andapplying the bead ofan adhesive material includes covering the side surface and a peripheralportion of the first surface of each said device with the bead material.31. The method of claim 30, wherein the first surface of the substrateis substantially planar.
 32. The method of claim 30, wherein the firstsurface of the substrate is planar.
 33. The method of claim 32, whereinseparating such bead packages includes cutting the substrate.
 34. Themethod of claim 30, wherein separating the packages includes splittingeach bead and splitting the substrate.
 35. The method of claim 34,wherein splitting each bead and splitting the substrate includes cuttingthe bead and substrate with a saw.
 36. The method of claim 30, furthercomprising electrically connecting a bond wire between each integratedcircuit device and the electrical conductor of the site for therespective integrated circuit device; andapplying the bead of viscousadhesive material onto the first surface of the substrate so that eachsaid bond wire is covered by the bead material.
 37. The method of claim36, wherein separating the packages includes splitting each bead andsplitting the substrate.
 38. The method of claim 37, wherein splittingeach bead and splitting the substrate includes cutting the bead andsubstrate with a saw.
 39. A method of making a plurality of integratedcircuit packages comprising:providing a substrate having a firstsurface, an opposite second surface, and an array of sites each adaptedfor the formation of an integrated circuit package; wherein each sitehas an electrical conductor extending through said substrate between thefirst surface and the second surface of the substrate; providing anintegrated circuit device for each site of the array, wherein eachintegrated circuit device has a first surface having a light sensitiveportion, and an opposite second surface; placing the second surface ofone of the integrated devices onto the first surface of the substrate ateach site; electrically connecting the integrated circuit device placedon each of the sites to the electrical conductor of the respective site;applying a bead of a viscous adhesive material onto said first surfaceof the substrate around each integrated circuit device, so that eachintegrated circuit device is in a cavity formed by the bead and thefirst surface of the substrate; hardening the adhesive bead; applying alayer of a transparent adhesive material onto the first surface of eachintegrated circuit device and within each cavity; hardening saidtransparent adhesive material; and splitting the bead material and thesubstrate between the package sites so as to separate individualpackages.
 40. The method of claim 39, wherein splitting the beadmaterial and splitting the substrate includes cutting the bead materialand substrate with a saw.
 41. The method of claim 39, further comprisingelectrically connecting a bond wire between each integrated circuitdevice and the electrical conductor of the site for the respectiveintegrated circuit device; andapplying the bead of viscous adhesivematerial onto the first surface of the substrate so that each said bondwire is covered by the bead material.
 42. The method of claim 41,wherein splitting the bead material and splitting the substrate includescutting the bead material and substrate with a saw.
 43. The method ofclaim 39, wherein each integrated circuit device has a side surfacebetween the first and second surface of the integrated circuit device;andapplying the bead of an adhesive material includes covering the sidesurface and a peripheral portion of the first surface of each saiddevice with the bead material.
 44. The method of claim 43, whereinsplitting the bead material and splitting the substrate includes cuttingthe bead material and substrate with a saw.
 45. The method of claim 43,further comprising electrically connecting a bond wire between eachintegrated circuit device and the electrical conductor of the site forthe respective integrated circuit device; andapplying the bead ofviscous adhesive material onto the first surface of the substrate sothat each said bond wire is covered by the bead material.
 46. The methodof claim 45, wherein splitting the bead material and splitting thesubstrate includes cutting the bead material and substrate with a saw.